1. Technical Field
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel in which a sustain discharge can be induced by an opposed discharge.
2. Related Art
Generally, a plasma display panel (PDP) is a display device in which vacuum ultraviolet (VUV) rays emitted from plasma by gas discharge excite phosphors to generate visible light, thereby creating images. Such a plasma display panel having a high-resolution large screen has been in the spotlight as a next-generation thin display device.
In the structure of the plasma display panel, a three-electrode surface-discharge structure is generally used. The plasma display panel having the three-electrode surface-discharge structure includes a front substrate that has display electrodes, each including two electrodes, and a rear substrate that is spaced apart from the front substrate at a predetermined distance and includes address electrodes. A space between the substrates is divided into a plurality of discharge cells by barrier ribs. In each discharge cell, a phosphor layer is formed on the rear substrate. Discharge gas is injected into the discharge cells.
Whether or not a discharge is generated is determined by an address discharge between one of the two electrodes of the display electrode and an opposing address electrode. A sustain discharge that controls luminance is generated by two electrodes in the display electrode that are disposed on the same surface. That is, in conventional plasma display panels, the address discharge is induced by an opposed discharge and the sustain discharge is induced by a surface discharge.
Though the distance between the display electrode and the address electrode is larger than the distance between the display electrodes, a discharge firing voltage of the address discharge is smaller than a discharge firing voltage of the sustain discharge. It has been known that, since the address discharge is induced by an opposed discharge, the discharge firing voltage of the address discharge is smaller than that of the sustain discharge which is induced by a surface discharge. Accordingly, it can be seen that a plasma display panel capable of generating the sustain discharge by an opposed discharge has higher efficiency than the conventional plasma display panel.
A discharge space in a display panel is divided into a sheath region and a positive column region by the discharge generated in the plasma display panel. The sheath region is a non-light-emitting region, which is formed to surround the electrode or the dielectric layer and in which most of voltage is consumed. The positive column region is a region in which the plasma discharge is quickly generated by a very small voltage. Accordingly, in order to increase the efficiency of the plasma display panel, it is important to enlarge the positive column region. Because the length of the sheath region is not related to the discharge gap, the discharge length may be increased to enlarge the positive column region. However, if the discharge gap is enlarged to extend the discharge length, a problem is created in that the required discharge firing voltage is increased.
As such, in the conventional plasma display panel, a low discharge firing voltage and a high efficiency cannot be achieved simultaneously.